I am posting this repair job on the engine mount removal on my 1984 300TDT. I had previously done the job on my older 240D and don't remember it being a particularly difficult job. It is a very different story on the 5 cylinder TDT wagon.The FSM and the Haynes manual were of limited help. Haynes just says support the engine and remove the bolts to replace the mount.I saw little helpful info on the net and in the forums. Kent Bergsma's you tube videos were informative but accessing his help required buying the mounts and new bolts and thread chasers and a variety of tools which I already owned. It is probably possible to do this job without a lift on a creeper and jack stands but I would not attempt it at my age without my Bendpak car lift and I don't crawl under cars on jack stands. First remove the radiator shroud clips and the throttle rod attached to the firewall to avoid damage as you lift the engine from below. Put a bottle jack and a big slab of thick wood under the oil pan . Try to loosen the 12X40 mm 8mm socket allen bolts attached to the aluminum support arms. If they come out relatively easy, continue. I found it necessary to lift the engine a tiny bit to take some of then tension off the mounts. Once removed you jack the engine up enough(3-5 inches) to remove the shields. The next step is to remove the 6 mm socket bolts. The passenger side is easy.Access is good from above and below with socket allens and regular allens. I did it from below standing on the floor with a good light and a mirror. The driver side is the hard one. You need to remove the engine shock on that side to get access to the inside socket bolt. Remove the plate on the topsiide end of the shock held on by short 10 mm bolts. Unscrew the 10 mm nylok nut on the bottom of the shaft. Use a 7mm open end to keep the shaft from spinning. It is visible at the very bottom of the shaft on a bracket best seen with a mirror. Once the shock is pulled out along with the rubber mounts and washers you have some access to the pesky inside bolt but you can't jack the engine too high or you hit the oil cooler line. It required all the 6mm tools and was time consuming. Clean and examine all the bolts and holes. My old mounts had collapsed almost 3/4" and were very hard. The vibration at idle was significant. The other difficulty was inserting the 8mm bolts to the engine bearers which required moving the engine sideways and forwards with a variety of 2x2's and pry bars.. All the rubber components are shot on this 37 yr old car and that is the next task. The engine is now smooth vibration free and quiet as a Tesla.

I've never seen a diesel Mercedes as quiet as a Tesla. That is pretty impressive.

Dkr.

To get it quiet as a Tesla you have to turn the key to the left.